The range of y = x squared + 2x / 3 squared - 4 is

The range of y = x squared + 2x / 3 squared - 4 is

y=2x^2/(x^2+3)+4
=[2(x^2+3)-6]/(x^2+3)+4
=2-6/(x^2+3)+4
=6-6/(x^2+3)
x^2+3>=3
So 6 / (x ^ 2 + 3)